Spindle mounting



March 8, 1927,Y

A. TURNER ET-AL SPINDLE MONTING Filed A1192. 9, 1925 IHHHI lllll A tto/"nay Patented Mans, 1927.

UNITED srarlss "PATENT OFFICE.

ALBERT TURNER AND ALFRED 1". BURNS, 0F WORCESTER, MASSACHUSETTS, AS-

SIGNORS T0 THE HEALD MACHINE GOIMIPANY, 4Oll WORCESTER, MASSACHUSETTS,

'A CORPORATION or MASSACHUSETTS.

SPINDLE MOUNTING.

Application mea August s, 1923. seriai No. 656,430.l

Our invention relates to an improved ing had to the accompanying drawings, in'v l' mounting forspindles or shafts, especially `Whichas employed-- in grinding and other similanbfhig. 1` is a. vertical sectional view of a machines for rotating a wheel or tool While in engagement with surface of a piece of work. j

In grinding and other similar operations, it is of advantage to take a heavy initial cut on the piece of work, and then to reduce the depth of out as the work is gradually brought to size and finished. Under such conditions of operation, the bearing support for the wheel or tool spindle must be capable of withstanding the lateral strains imposed thereon when taking a heavy cut, without becoming worn to such an extent as to make it impossible for the wheel or tool to make a light cut with the desired accuracy. Ordinary .sleeve bearings and also anti-friction roller or ball bearings have both been heretofore separately employed for'supporting the wheel spindles of grind ing machines and the rotary tool spindles in other similar machines, and while it has been found that ball or roller bearings are better able to withstand severe lateral strains on the spindle than are ordinary sleeve bearings, it has been found also. that the small amount of lateral play permitted by rolling bearings, renders it difficult to take the light 'finishing cuts as accurately as when using sleeve bearings.

By the present invention, we provide an improved mounting for grinding wheel 0r rotary tool spindles, by means of which it is possible to support such a spindle, as the operator may desire, either in rolling bearings or in sleeve bearings, depending upon A the nature of tlie cut being taken by the wheel or tool. By the use of our improved spindle mounting, it is possible, whenever desired, to change from the support of the spindle with rolling friction, to the support of the spindle with sliding friction, and vice versa, without. requiring the removal, .or rearrangement of any of the parts of the machine, and without materially affecting `the adjustment f the wheel or tool with respect to the work. The above and other advantageous features of our invention will lhereinafter more full appear, reference be- -of balls 15 is' arranged between the inner The drawing shows thrinvention vas a 4 'plied to a grinding machine spindle 1, t e

latter providing at one end a grinding wheel .2, and being rotatably supported in suitable larms 3iL and 3b, provided by the'usual wheel head or slide 4 of the machine. A pulley 5 is mounted on the spindle 1 intermediate its ends, whereby the spindle may be driven from a suitable source of power, not shown, 4and the slide 4 is capable of lateral movement in order to feed the spindle 1 and the wheel 2 toward and from the work.

The spindle 1 is susceptible of finding its support in one orthe other of two diii'erent sets of bearings, and for purposes of. illustration, the parts of our improved `'75 mounting are shown in such a position as to support the spindle 1 in the rolling bearings, the change from support of the spindle 1 in the rolling bearings toits support in the sleeve bearings being carried out in a manner which will be hereinafter described.

The spindle 1 at the portions marked 6 and 7 is encircled by inner annular ball races 8 and 9, respectively. A series of balls 10 is circumferentially arranged between the inner race 8 and an outer ball race 11, which is held against a shoulder 12 provided in the cylindrical bore 13 of the arm 3 by means of a clamping plate 14. The interior surface of the outer race 11, from the portion normally in engagement with the balls 10, is of gradually increasing diameter on the innermost side of said balls, as lshown at 11a, Fig. 1. A second series c5 race 9 `and an outer ball race 16, which is received in a cylindrical counterbore 17 pro# vided in the arm 3". The inner surface of the outer race 16, from the portion normally in engagement withthe balls 15, is of gradl ually increasing diameter on the innermost sideof said balls, as shown at 16", Fig. l.

In other words, both ball bearings can conveniently be of the well known cup and cone type, since the characteristics of this type lend themselves particularly to the purposes of our invention as will presently `appear.

The outer surface of the ball race 16 has a sliding lit within the counterbore 17, find a plurality of springs 18 engage the edge of the race 16 and serve to maintain it in engagement with a plurality of rods 19, 19 projecting into the counterbore 17, ,said rods being slidable in the arm 3b. The springs 18 are received in suitable seats 20 provided in a plate 21 secured to the arm 3". The position of the ball race 16 within the counterbore 17 is thus determined by the amount which'the rods 19 extend into the counterbore 17.

The rods 19 are carried by a plate 22 provided with a recess 23, within which is re-V ceived the head 24 of a bolt 25. .The shank of the bolt 25 is in threaded engagement with the central hub 26 of a cap 27 secured to the arm 3", and the end of the bolt 25 is provided with a tool receiving slot 28, whereby the bolt 25 may be turned to cause movement of the plate 22 with respect to the cap 27. A nut 29 is provided to lock the bolt 25 against turning movement, after thedesired adjustment of the plate22 has taken place.

The plate 22 is connected to a yoke mem-4 ber 30, which embraces a head 31 provided on a reduced portion 32 of the spindle l. The yoke is annular in form and its outer periphery fits closely within the main bore 33 of the arm 3b. Movement of the plate 22 and the yoke 30 by means of the bolt 25, is l adapted to cause longitudinal movement of the spindle ,1 when it is desired to change from support of the spindle 1 by ball bearings to support of the spindle by sleeve bearings, or vice versa, as will now be described.

AV sleeve bearing is received within the bore 13 of the arm 3, and as best shown in is made in two parts, 34:av and 34h.,

Fig. 2, The parts are so proportioned that the weight of the spindle l is taken olf the lower bearing portion 34, when the spindle 1 is supported by theball bearings, as shown 'in Fig. 1. Springs 35 exert their pressure tomaintain the bearing portion 34 in engagement with the spindle 1, said springs being seated in adjustable' members 36-threaded. within openings provided in the bearing caps 40, 40. Lower and upper bearing portions 37a and 37b are received within the bore '33, in precisely the same manner as the bearing portions 34* and 34 of bore 13.

When the spindle is `driven with the parts in the positions shown in Fig. 1, the balls 10 and 15 take the entire load, and this is the preferable mode 'of operation when the grinding wheel 2 is taking a heavy cut. When it is desired to takea light or finishing cut with the wheel 2, thefsupport of the spindle is shifted from the ball bearings to the sleeve bearings by turning the bolt 25 so as to cause the plate 22 and the yoke 30 to be drawn to the right.- It willbe noted that with the parts in the position shown in Fig. 1, there is a clearance space 38 between the yoke 30 and the head 31 on the spindle 1, so that the plate 22 will first be moved without moving the spindle 1 with it. As the plate 22 is drawn to the right, the rods 19 move with it, thus allowing the springs 18 to shift the outer ball race 16 to the right, and bringing the portion 1Ga opposite the Sil ballsvl; this transfers the load onto the oil film of the sleeve bearing portion 37a.

Continued turning of the bolt 25 causes the yoke 30 to engage the head 31 of the Spindle 1 and thus draws the spindle 1 longitudinally to the right. When this occurs the inner ball race 8 moves with the spindle 1, thus bringing the balls 10 opposite the outer race portion 1 a, and rendering said outer race ineffective; this completes the transfer of the load onto the oil ilm of the sleeve bearings, which is the preferable mode of operation for the wheel 2 to take a light cut with extreme accuracy, since the sleeve bearings steady the spindle, and prevent it from chattering. As will be apparent, an opposite movement of the bolt 25, to shift the parts to the left, restores the ball bearing support and relieves the load from the sleeve bearings. It will be understood of course that in shifting from .either mode ofv support to the other, the members 36, 36 are arrangement of the partsof a. grinding machine, it is obvious that-it is not so limited' in its application, but can equally well be employed in connection with the support of a ind1e carrying any kind of rotating tool.

-1. In a device of the class described,` a spindle, a. ball bearilg associated therewith, a sleeve bearing, in e bearing or the races thereof, also associated with said spindle, and means for interehangeably rendering one or the other of said bearings operative, while maintaining the same assembly of parts.

pendent of said ball solo@ 2. In a device of the class described, a tool carrying spindle, a series of circumferentially arranged4 bearing members for rotatably supporting said spindle with rolling friction, a cylindrical bearing member or rotatably supporting said spindle with friction, and selective means for shifting said spindle axially to transfer its support interchangeably from one type of bearing member to the ciber.,

3. ln a device oi the class described, a tool carrying spindle, a series oi circumferentially arranged bearingmembers for rosupporting said spindle with rolling hic-tion, a cylindrical bearing member for Irotatably supporting said spindle with sliding iction, and manually operated means for sbiiting said spindle axially to transfer its support interchangeably from the rolling aring members to tbe cylindrical bearing members.

d. lne device of tlie class described, a tool carrying spindle, a series of circumferentially arranged bearing members for rotatablyr supporting said spindle with rolling friction,

cylindrical bearing member for rotatably supporting said spindle with sliding friction, and manually operated means foi-.shifting 1the axis oi rotation of said spindle to transer its support interchangeably lfrom one type of bearing member to the other.

5. In a device of tlie class porting member baring a cylindrical bore extending therethrough, a tool carrying spindle received in said bore, a series of cireumi'erentially arranged bearing members for rotatably supporting said spindle within said bore, a cylindrical bearing member for rotatably supportingy said spindle, and mannelly operated means for causing relative described, a supmovement in the direction of tbe spindle anis` Y between said circumferential bearing inembers and said spindle, to interchangeably shift the support of the said spindle from one type of bearing member to the other.

6. The combination with a rotary spindle, of ball bearing supports land sleeve bearing supports independent of said hall bearing supports therefor, and means for selectively and interebaneabl rendering operative one or the other o? saidvsupports.

7. The combination with a rotary spindle adapted for support in cap and cone bearings'oi sleeve bearings independent of said cup and cone ior said spindle, and means for rendering the latter operative or inoperative by relative movement between the parts of said ball bearings.

8. ln a device oi the class described, .a supporting member having acyiindrical bore therethrough, a ltool carrying spindle received in said bore, a series oi ein cumferentially arranged bearing members i'or rotatably snpporn said spindle by rolling friction within sai bere, races ior said circumferential@ arranged bearing members, a bottom bearing segment for said spindle entirely independent of said races and rigidly bald said bore, and means for displacing said circumierentially arranged bearing' members so as to allow said spindle to rest on said bottom bearing segment.

9. In a device oi tbe class described, a supporting member liavinga cylindrical bore extending tlieretlirongli, a tool carrying spindle received in said bore, a series of eircumerentially arranged bearing members for rotatably supporting said spindle by rollingriction Witbin said bore, races for said circnml'ferentially arranged bearing members, a bottom bearing segment for said spindle entirely independent ol said races and rigid- 1 ily beld witbin said bore,

means for displacmg 'said cireumfcrentially arranged bearing members so as to allow said spindle to rest on said bottom bearing segment, and a top segment adapted thereupon to automatically descend upn said spindle.

10. In a device of the class described, a supporting member a cylindrical bore extending therethrough, a tool carrying spindle received in said bore, a series o cirenmierentially varranged balls for rotatably supporting said spindle by rolling friction said bore, races for said circumferentially arranged bearing balls, a bottom bearing segment for said spindle entirely independent of said races and rigidly bel-fl within said bore, so as to allow said bottom bearing spindle to rest on said segment.

ALBERT TURNER. ALFRED IBURNS.

and means for displacing said balls .ma 

